Add on head rest



FIG. 1 is a bottom isometric view of the ornamental head rest;

FIG. 2 is a rear view;

FIG. 3 is a right side view;

FIG. 4 is a left side view; and,

FIG. 5 is a top view.

FIGS. 2 and 4 have been shown on an enlarged scale with respect to theother views. The head rest has been lined in the drawing views withhorizontal lines to represent the color blue and the strap and fastenershave been lined with crossed lines to represent the color black.

The ornamental design for an add on head rest, as shown and described.